A swell packer typically includes a swellable material positioned around tubular member (e.g., a base pipe). When the swell packer is initially run into a wellbore, an annulus is defined between the swellable material and an outer tubular member such as a liner, a casing, or a wall of the wellbore. The swell packer may be submerged in a liquid in the wellbore, and after a predetermined amount of time in contact with the liquid, the swellable material may swell radially-outward and into contact with the outer tubular member to seal the annulus.
When assembling the swell packer, the swellable material is oftentimes adhered to the outer surface of the tubular member with end rings at a bespoke facility. In other embodiments, the swellable material is sleeved over the tubular member and held in place with end rings. The end rings may be clamped or fastened to the tubular member.
In other cases, the swellable material is bonded to a custom pup joint with end rings installed, specially manufactured for the application. The pup joint is then connected and run as part of the string of tubulars in the well. While pup joint embodiments may be employed successfully in high-pressure environments, the custom design thereof for each different type of tubing string, tubing size, etc., may be expensive and present inventory management issues.
The elastomer in swell packers is designed to swell in a specific medium over a specified time. Once in the medium, the process typically cannot be halted. As a result, any deviation in well construction time as the packers are being run may present a problem as the swell process may occur before the desired time.